1. Field of the Invention
This invention relates to a liquid crystal display device having a liquid crystal composition held between a pair of electrodes and a method of manufacturing the liquid crystal display device, and more particularly to an improvement in the electrode structure of a liquid crystal display device.
2. Description of the Related Art
Recently, liquid crystal display devices have been used as TV or graphic display devices in various technical fields, since they are compact, light, and of low power consumption.
Various types of liquid crystal display devices are available, for example, a simple matrix type display device employing pairs of stripe electrodes arranged in the form of matrix, and a liquid crystal composition held between each pair of stripe electrodes; an active matrix type display device employing a switching element provided for each display pixel.
In each of the liquid crystal display devices, it is necessary to make at least one electrode substrate of each electrode pair transparent. That is, in each pair, at least one electrode must be light transmissible, as well as its substrate.
As transparent materials for the electrode, an NESA (stannic oxide) film and an I.T.O. (Indium Tin Oxide) film are well known. In particular, demand for an I.T.O. film as a transparent electrode material has increased, since it can be easily patterned in a photoetching process or the like, as compared with other transparent electrode materials, and it has a high light transmittance and electrical conductivity.
However, the I.T.O. film contains indium (In), which is a very rare metal, and which is hard to collect. Therefore, development of transparent electrode materials to be used in place of the I.T.O. film have actively been pursued these years. Further, development of a liquid crystal display device has been requested, which has an electrode structure made of a low-cost material in place of I.T.O. and having a high light transmittance.